The technology disclosed generally relates to the field of manufacture and assembly of circuit boards. More specifically it relates to structure for delivering component tape to a component pickup position at which a component mounting machine removes components from the carrier tape for placement on a circuit board.
Generally, within the field of manufacture and assembly of circuit boards, electronic components are fed to a component mounting machine for mechanically and/or electrically mounting the components onto a circuit board. These surface mounted components are often delivered spaced apart along the length of a component tape, which consists of a lower carrier tape provided with compartments, one for each component, and an upper cover, or cover tape or protective tape.
After positioning the electronic components in the corresponding compartments, the cover tape is attached to the carrier tape, and the component tape is wound on a component reel. The attachment of the cover tape to the carrier tape can, for instance, be performed by providing either the cover tape or the carrier tape with adhesive areas, or by fusing the cover tape to the carrier tape. Then, the component reel is transferred to a component mounting machine, which feeds a component to a certain predetermined picking position where it can be picked, or collected, by a pick-up head. WO 1986/00778 shows a cassette magazine for a component mounting machine using the above described method.
According to a method conventionally used within the art, the loading of a component tape in a component mounting machine involves the following steps. Placing the component tape reel into the tape holder of a component mounting machine, or into a tape magazine of a component mounting machine; introducing the free end of the component tape into a feeding mechanism, provided in the machine or in the magazine, such that feeding pins engage corresponding holes provided in the component tape; separating, e.g. by hand, the end of the cover tape from the end of the carrier tape for a distance sufficient for the cover tape to be engaged with a cover tape handling means; and lowering a locking mechanism over the carrier tape for holding the carrier tape against the feeding mechanism.
Prior to the picking of the components, each component has to be exposed so as to make it available for picking. Conventionally, this is achieved by removing the cover tape from the carrier tape. The cover tape is then fed away by a separate cover tape handling means in order for the cover tape not to disturb the picking of components. Generally, the cover tape handling means comprises a winding hub on which the cover tape is wound. Additionally, when unloading the component tape from the component mounting machine, or the tape magazine, the winding hub has to be cleared of the cover tape.
A considerable length of the end of the cover tape has to be separated from the end of the carrier tape in order to bring the cover tape end to a cover tape handling means. Thus, the first decimeters of a new carrier tape are typically not provided with components. Otherwise, numerous components would be wasted during loading. However, when reloading a tape reel that already has been partly used, the tape is provided with components throughout, and consequently a large number of components may be wasted.
Prior art solutions describe a component tape comprising a carrier tape provided with compartments filled with components and a cover tape introduced into a feeding mechanism. Pins of feeder heads, mounted in the tape magazine, engage corresponding holes provided in the carrier tape. The end of the cover tape is removed from the carrier tape and wound onto a winding hub, which is provided with a separate feeding mechanism. The cover tape is brought past a first plate provided with a stripping edge, and the cover tape may be stretched by a separate reel applying pressure on the cover tape. A second plate may be provided after the first plate for preventing small components that can be electrostatically adhered to the cover tape from sticking to and following the removed portion of the cover tape when said portion is fed away. The second plate extends to a position where the components are picked by a pick-up head.
U.S. Pat. No. 7,220,620 discloses a system where the tape guide is provided with means for exposing a component to be picked at a picking position. This exposure means comprises separating means for separating and lifting a lateral portion of the cover from the carrier tape, leaving the remaining portion of the cover at least partially attached to the carrier tape, and for bringing the lifted portion of the cover aside such that the component to be picked can be exposed.
The use of such separating means in U.S. Pat. No. 7,220,620 eliminates the need for means handling the cover tape after removal from the carrier tape since the cover remains attached to the carrier tape.
The previously discussed tape feeders and tape guides may not be suitable for use when the component is contained within a deep compartment in the carrier tape. Specifically, the tape feeders in combination with tape guides are typically not adapted to allow a picker to remove the component from such deep compartments. Therefore there exists a need for structure that allows for the picking of components within deep compartments in carrier tape. Furthermore, the previously discussed tape guides are not adapted for use with various tape feeders that accommodate wide ranges of tapes with varying widths. Therefore, in order to improve manufacturing efficiency and operational flexibility, there exists a need for a tape guide that is capable of operating with a wide range of tape feeders such that a different tape guide does not have to be used with each specific tape feeder in order to accommodate the different widths of tape that each tape feeder utilizes.
The magazine slots of state of the art component tape magazines are typically not capable of operating with different types of tape feeders carrying component tapes with different widths, and/or tape feeders that are capable of operating with a wide ranges of tapes having varying width, since each tape feeder position or slot is only capable of operating with a specific type of tape feeder suitable only for carrying tapes with a certain limited width range. Therefore, in order to further improve manufacturing efficiency and operational flexibility, there exists a need for a component tape magazine having a plurality of slots or positions for accommodating tape feeders, which are each configured to accommodate and operate with different types of tape feeders and/or tape feeders which are configured to accommodate component tapes with a wide range of widths.